Electric switch.



PATENTED FEB. 28, 1905.

W. H. POWELL. ELECTRIC SWITCH.

APPLICATION FILED NOV. so, 1903.

2 SHEETS-SHEET 1.

[my 372607": 1 Wz'ZZz'a zn HPowaZZ fftorzzey No. 788,978. PATENTED' FEB. 28, 1905. W. H. POWELL.

ELECTRIC SWITCH.

APPLICATION FILED NOV. 80, 1903.

2 SHEETS-SHEET 2.

I WWSSw: I Ina 6705075 WZk M WzLZlz'a JnliPon ca M 1 ww UNITED STATES Patented. February 28, 1905,

PATENT QEEICE.

VILLIAM H. POWELL, OF EAST ORANGE, NEW JERSEY, ASSIGNOR TO CROCKER- HEELER COMPANY, OF AMPERE, NEW JERSEY, A COR- PORATION OF NEWV JERSEY.

ELECTRIC SWITCH.

SPECIFICATION forming part of Letters Patent No. 783,978, dated February 28, 1905.

Application filed November 30,1903. Serial No. 183,177.

To (all mil/0777, it 7771a (WU/0GP! Be it known that I, WILLIAM H. POWELL, a citizen of the United States of America, and a resident of East Orange, county of Essex, and State of New Jersey, have invented certain new and useful Improvements in Electric Switches, of which the following is aspecilication.

This invention relatesto an improved arrangement of Inulti1')le-voltage contact-rings for an electric-switch cylinder and also an improved arrangement of reversing contactrings for a switch-cylinder. Both the multiple-voltage contact-rings and the reversing contactn'ings are sectional and are supported on the convex surface of a cylindrical core of insulating material, and the contact-fingers are so positioned as to permit an arrangement of the contacts which are grouped on each section such that the sections can have substantial forms which will have a stable bearing on the cylindrical core. The invention is also such as to permit the adoption of inter changeable methods of construction by which the sections can be formed and finished before assembling on the core and any section of any contactring can be conveniently removed without having to detach or disturb other sections, thus affording a construction wherein the sections with contacts which are liable to wear or injury can be readily removed and replaced by new sections of the contact rings, which are interchangeable with the sections that are removed.

This invention has been designed with reference to its applicabilityin a switch to be used in connection with the system of electricmotor control set forth in United States Letters Patent No. 735,352, granted August 4:. 1903, on an application by Gano S. Dunn, and United States Letters Patent No. 736,587, granted August 18, 1903, on an application by Gano S. Dunn and Edwin R. Douglas. The applicability of the invention, however, is quite general and is particularly important in controllers which make a large number of different electrical connections and have a large number of circuit positions or steps,

thereby requiring a cylinder of considerable circumference in comparison with the general size and weight of the contactrings. The reversing contact-rings are particularly applicable in a switch wherein the forward-speed positions exceed the reverse-speed positions.

In the accompanying two sheets of drawings, which form a part of this application, Figure l is an elevation of a switch cmbodying my invention, the inclosing casing being broken away. Fig. 2 is a development of the switch-cylimler, showing the developed surface of the core and the contact-rings and electrical connections. Fig. 3 is a perspective view of one of the multiple-voltage contactrings. Fig. A is a perspective view .of the other multiple-voltage contact-ring. Fig. 5 is a perspective view of the reversing contactrings.

The switch herein illustrated is provided with contacts for effecting the shifting of the connection of the armature and series lield leads of a compound-wound motor M between four conductors a I 0 (Z, which have different potentials maintained between them, and hence are the supply-conductors of a multi plevoltage system. The switch is also provided with contacts for effecting changes in the shunt field-winding of the motor by introducing resistance into the field-circuit in the manner and in the sequence set forth in the second Letters Patent above referred to. The switch also is arranged to supply current to the armature at four of the potentials in reverse directions for reverse movement, but without thefield-variation features, and hence at fewer positions, requiring less angular movement. hen the switch is operated, the armature and series field-circuit is from the contact-linger on one or the other of the supply-conductors a Z) 0, according to the operated position of the switch, as set forth in the above-men tioned patents. to one of the two multiplevoltage contact-rings, which in the form herein disclosed is in two sections 0 m Thence from the contacts of this ring the circuit is to a multiple-voltage contact-linger of a short connection f, thence through a contact-linger on also in two sections r r to one or the other 1 of two eontact-fingers A or AA at the ends I the motor-armature leads. accordingly as the contacts at the left or the right of the line of contact-fingers are brought under the fingers, thence through the connected leads and the armature to the other lead and contact-finger, thence from this contact-finger to the other reversing contact-ring, also in two sections it /t, to a contactfinger on the end of a lead from the series field, thence from this contact-finger and lead through the series field-coils and the other lead to its multiplevoltage contactfinger f on the end of the lead, thence from this contact-finger to the other multiple-voltage contact-ring, also in two sections Z1 Z", to a supply-conductor contact-finger on one or the other of the supplyconductors Z) 0 (Z, the latter connection to the leads being as set forth in the above-mentioned patents. The two multiple-voltage contact-rings effect connections by which one of several voltages is supplied over the circuits and connections above traced between the two above-mentioned multiple-voltage contact-lingers, and these lingers are termed multiple-voltage contact-fingers to distinguish them from the contact-fingers which are terminals of the supply-conductors, each of which is maintained at a fixed potential. The shunt-field is varied by contacts on a field-varying contact-ring consisting of two sections Z Z. The connections are as set forth in the second of the above-mentioned patents when the contacts at the left of the line of contact-fingers in Fig. 2 are brought under the fingers, and provision is thereby made for twenty-three different speeds. The contacts at the right, which are for reverse movement, are not combined with field-variation contacts, and provision is only made for four positions at the first four of the voltages at full field strength, since reverse movement is not so important, and under one-fifth of the circun'iference is required for the reverse contacts, leaving four-fifths of the circumference for the forward contacts. The contactrings are mounted on a core of insulating material or, which is circumferentially grooved at (1 o and longitudinally grooved at y) 7). There is a circumferential groove for each set of contacts and two longitudinal keyways on opposite sides of the core. Each of the sets of contacts of each ring almost completely surrounds the switch, and each ring is divided into two sections, and each section has a tongue w, preferably integral with the section, which projects inwardly from its concave side and engages an underlying circumferential groove. As the function of each contact-ring element of the cylinder and there is no eleceach ring is divided or split into two sections, and each section occupies approximately a semicircle or less, so that it can be fitted onto the circumferentially-grooved core. transverse keyway r is formed in the concave surface of each section of each of the contactrings and is cut through the tongue formed thereon. This keyway overlies one or the other of the longitudinal grooves in the core. A key 1', which is of fiber or other suitable insulating material, secures the ring on the core against circumferential displacement. Two longitudinal grooves and keys are suliicient for all the sections, since each section approximately covers a semicircle, and the two longitudinal grooves can be readily located so that each of the sections will overlie one or the other of the keys. These are shown in the development of Fig. 2. In addition to the tongues and keys to prevent longitudinal and circumferential displacen'ient of the sectional contact-rings screwsx pass through the sections into the core and secure the sections to the surface of the core.

The two sets of multiple-voltage contactrings each carry four Cll'CLllDfGl'Ol'ltlttl rows of contacts. Three of the rows contact with the contact-lingers of the supply-coraluctors, and these rows each carry contacts at but a few points of the circumference of the switch. The other row contacts with a multiple-voltage contact-finger and has contacts at each operated position of the switch throughout the circumference. This ring 1 preferably make one of the intermediate rows and locate the tongue under this row in each contactring section, since the tongue if located under this row can be the entire length of the section and serve as a rib near the medial line of the section, so that the section will have a more con'ipact and solid form and will have a more stable seat on the core. The points of the circumference where the rings are divided into sections is determined by structural rea sons, since the electrical separation of the parts of the rings is immaterial, it being mainly necessary that the two points of division of any one ring shall be about opposite, so that neither section will embrace more than a sen'iicircumference, or but slightly more, in order that it may be removed without having to take off other rings and slip it oll the end. Two rings are required for effecting the reversal of connections to the armature-leads in passing the off position, and each ring has two parallel rows of contacts on both sides of the off position. One of the sections, l1, is formed in two branches lying on opposite sides of the off position, one of these branches being forked. Each of the two forks 11 carries a row of contacts, and the two branches of the semicircular contactring section which is is only to bridge contact-fingers on the same formed lie on opposite sides of the off position. By this construction it will be seen trical reason for continuity circumferentially, i that electrical connection is provided between the two separated rows of contacts on the forks. One of the sections, g, of the other ring also has two branches, one of which lies between the forks of the forked section of the other ring and carries contacts for all the reverse-operated positions, and the other branch of which carries contacts for some of the forward-operated positions of the switch. These forward and all the reverse positions are included within a semicircle. The two branches of this section are offset with respect to each other, so that only one of the two rows of contacts in one branch alines circumferentially with one row of contacts in the other branch. By this construction it will be seen that contacts for both forward-operated and reverseoperated positions of the switch are provided on the same section, and this is true both with respect to the forked section and the offset section. The number of sections necessary to carry all the contacts which are required for effecting reversal is thereby reduced to a minimum.

hat I claim as new, and desire to secure by Letters Patent of the United States, is-- 1. .In an electric switch, the combination of a plurality of contact-fingers between which different potentials are maintained, a multiple-voltage contact-finger intermediate of the other contact-lingers, and a contact-ring provided with contacts in separate rows for each contact[inger, substantially as described.

2. In an electric switch, the combination of a cylindrical core of insulating material, a reversing-contact-ring section formed .in two branches one of which is forked, each branch being provided with parallel rows of contacts, the forked branch having a row on each fork, and a second reversing-contact-ring scction formed in two branches offset with respect to each other, each branch being provided with parallel rows of contacts, and one branch litting between the forks of the forked contact ring section, substantially as described.

3. In an electric switch, the combination of a cylindrical core of insulating material, a plurality of forward-speed contacts, a lesser number of reverse-speed contacts, a reversingcontact-ring section formed in two branches one of which is forked, each branch being provided with parallel rows of contacts, the forked branch having a row on each fork, and a second reversing-contact-ringsection formed in two branches offset with respect to each other, each branch being provided with parallel rows of contacts, and one branch litting between the forks of the forked contact-ring section, substantially as described.

Signed at East Orange, New Jersey, this 27th day of November, 1903.

\VlLLlAM H. POYVELL.

\Vitnesses:

SAMUEL W. B Loi-i, EDWIN RUsr DOUGLAS. 

